summaryrefslogtreecommitdiff
path: root/indra/llinventory/llpermissions.h
blob: b6071118ffccc9b15518d1d8d336db4c7d4cf54d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
/**
 * @file llpermissions.h
 * @brief Permissions structures for objects.
 *
 * $LicenseInfo:firstyear=2002&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#ifndef LL_LLPERMISSIONS_H
#define LL_LLPERMISSIONS_H

#include "llpermissionsflags.h"
#include "llsd.h"
#include "lluuid.h"
#include "llxmlnode.h"
#include "llinventorytype.h"

// prototypes
class LLMessageSystem;
extern void mask_to_string(U32 mask, char* str);
extern std::string mask_to_string(U32 mask);
template<class T> class LLMetaClassT;

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// Class LLPermissions
//
// Class which encapsulates object and inventory permissions/ownership/etc.
//
// Permissions where originally a static state creator/owner and set
// of cap bits. Since then, it has grown to include group information,
// last owner, masks for different people. The implementation has been
// chosen such that a uuid is stored for each current/past owner, and
// a bitmask is stored for the base permissions, owner permissions,
// group permissions, and everyone else permissions.
//
// The base permissions represent the most permissive state that the
// permissions can possibly be in. Thus, if the base permissions do
// not allow copying, no one can ever copy the object. The permissions
// also maintain a tree-like hierarchy of permissions, thus, if we
// (for sake of discussions) denote more permissive as '>', then this
// is invariant:
//
// base mask >= owner mask >= group mask
//                         >= everyone mask
//                         >= next owner mask
// NOTE: the group mask does not effect everyone or next, everyone
// does not effect group or next, etc.
//
// It is considered a fair use right to move or delete any object you
// own.  Another fair use right is the ability to give away anything
// which you cannot copy. One way to look at that is that if you have
// a unique item, you can always give that one copy you have to
// someone else.
//
// Most of the bitmask is easy to understand, PERM_COPY means you can
// copy !PERM_TRANSFER means you cannot transfer, etc. Given that we
// now track the concept of 'next owner' inside of the permissions
// object, we can describe some new meta-meaning to the PERM_MODIFY
// flag. PERM_MODIFY is usually meant to note if you can change an
// item, but since we record next owner permissions, we can interpret
// a no-modify object as 'you cannot modify this object and you cannot
// make derivative works.' When evaluating functionality, and
// comparisons against permissions, keep this concept in mind for
// logical consistency.
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

class LLPermissions
{
private:
    LLUUID          mCreator;               // null if object created by system
    LLUUID          mOwner;                 // null if object "unowned" (owned by system)
    LLUUID          mLastOwner;             // object's last owner
    LLUUID          mGroup;                 // The group association

    PermissionMask  mMaskBase;              // initially permissive, progressively AND restricted by each owner

    PermissionMask  mMaskOwner;             // set by owner, applies to owner only, restricts lower permissions
    PermissionMask  mMaskEveryone;          // set by owner, applies to everyone else

    PermissionMask  mMaskGroup;             // set by owner, applies to group that is associated with permissions

    PermissionMask mMaskNextOwner;          // set by owner, applied to base on transfer.

    // Usually set in the fixOwnership() method based on current uuid
    // values.
    bool mIsGroupOwned;

    // Correct for fair use - you can never take away the right to
    // move stuff you own, and you can never take away the right to
    // transfer something you cannot otherwise copy.
    void fixFairUse();

    // Fix internal consistency for group/agent ownership
    void fixOwnership();

public:
    static const LLPermissions DEFAULT;

    LLPermissions();                        // defaults to created by system
    //~LLPermissions();

    // base initialization code
    void init(const LLUUID& creator, const LLUUID& owner,
              const LLUUID& last_owner, const LLUUID& group);
    void initMasks(PermissionMask base, PermissionMask owner,
                   PermissionMask everyone, PermissionMask group,
                   PermissionMask next);
    // adjust permissions based on inventory type.
    void initMasks(LLInventoryType::EType type);

    //
    // ACCESSORS
    //

    // return the agent_id of the agent that created the item
    const LLUUID&   getCreator()        const   { return mCreator; }

    // return the agent_id of the owner. returns LLUUID::null if group
    // owned or public (a really big group).
    const LLUUID&   getOwner()          const   { return mOwner; }

    // return the group_id of the group associated with the
    // object.
    const LLUUID&   getGroup()          const   { return mGroup; }

    // return the agent_id of the last agent owner. Only returns
    // LLUUID::null if there has never been a previous owner (*note: this is apparently not true, say for textures in inventory, it may return LLUUID::null even if there was a previous owner).
    const LLUUID&   getLastOwner()      const   { return mLastOwner; }

    U32             getMaskBase()       const   { return mMaskBase; }
    U32             getMaskOwner()      const   { return mMaskOwner; }
    U32             getMaskGroup()      const   { return mMaskGroup; }
    U32             getMaskEveryone()   const   { return mMaskEveryone; }
    U32 getMaskNextOwner() const { return mMaskNextOwner; }

    // return TRUE if the object has any owner
    bool isOwned() const { return (mOwner.notNull() || mIsGroupOwned); }

    // return TRUE if group_id is owner.
    bool isGroupOwned() const { return mIsGroupOwned; }

    // This API returns TRUE if the object is owned at all, and FALSE
    // otherwise. If it is owned at all, owner id is filled with
    // either the owner id or the group id, and the is_group_owned
    // parameter is appropriately filled. The values of owner_id and
    // is_group_owned are not changed if the object is not owned.
    BOOL getOwnership(LLUUID& owner_id, BOOL& is_group_owned) const;

    // Gets the 'safe' owner.  This should never return LLUUID::null.
    // If no group owned, return the agent owner id normally.
    // If group owned, return the group id.
    // If not owned, return a random uuid which should have no power.
    LLUUID getSafeOwner() const;

    // return a cheap crc
    U32 getCRC32() const;


    //
    // MANIPULATORS
    //

    // Fix hierarchy of permissions, applies appropriate permissions
    // at each level to ensure that base permissions are respected,
    // and also ensures that if base cannot transfer, then group and
    // other cannot copy.
    void fix();

    // All of these methods just do exactly what they say. There is no
    // permissions checking to see if the operation is allowed, and do
    // not fix the permissions hierarchy. So please only use these
    // methods when you are know what you're doing and coding on
    // behalf of the system - ie, acting as god.
    void set(const LLPermissions& permissions);
    void setMaskBase(U32 mask)     { mMaskBase = mask; }
    void setMaskOwner(U32 mask)    { mMaskOwner = mask; }
    void setMaskEveryone(U32 mask) { mMaskEveryone = mask;}
    void setMaskGroup(U32 mask)    { mMaskGroup = mask;}
    void setMaskNext(U32 mask) { mMaskNextOwner = mask; }

    // Allow accumulation of permissions. Results in the tightest
    // permissions possible. In the case of clashing UUIDs, it sets
    // the ID to LLUUID::null.
    void accumulate(const LLPermissions& perm);

    //
    // CHECKED MANIPULATORS
    //

    // These functions return true on success.  They return false if
    // the given agent isn't allowed to make the change.  You can pass
    // LLUUID::null as the agent id if the change is being made by the
    // simulator itself, not on behalf of any agent - this will always
    // succeed. Passing in group id of LLUUID:null means no group, and
    // does not offer special permission to do anything.

    // saves last owner, sets current owner, and sets the group.
    // set is_atomic = true means that this permission represents
    // an atomic permission and not a collection of permissions.
    // Currently, the only way to have a collection is when an object
    // has inventory and is then itself rolled up into an inventory
    // item.
    BOOL setOwnerAndGroup(const LLUUID& agent, const LLUUID& owner, const LLUUID& group, bool is_atomic);

    // only call this if you know what you're doing
    // there are usually perm-bit consequences when the
    // ownerhsip changes
    void yesReallySetOwner(const LLUUID& owner, bool group_owned);

    // Last owner doesn't have much in the way of permissions so it's
    //not too dangerous to do this.
    void setLastOwner(const LLUUID& last_owner);

    // saves last owner, sets owner to uuid null, sets group
    // owned. group_id must be the group of the object (that's who it
    // is being deeded to) and the object must be group
    // modify. Technically, the agent id and group id are not
    // necessary, but I wanted this function to look like the other
    // checked manipulators (since that is how it is used.) If the
    // agent is the system or (group == mGroup and group modify and
    // owner transfer) then this function will deed the permissions,
    // set the next owner mask, and return TRUE. Otherwise, no change
    // is effected, and the function returns FALSE.
    BOOL deedToGroup(const LLUUID& agent, const LLUUID& group);
    // Attempt to set or clear the given bitmask.  Returns TRUE if you
    // are allowed to modify the permissions.  If you attempt to turn
    // on bits not allowed by the base bits, the function will return
    // TRUE, but those bits will not be set.
    BOOL setBaseBits( const LLUUID& agent, BOOL set, PermissionMask bits);
    BOOL setOwnerBits( const LLUUID& agent, BOOL set, PermissionMask bits);
    BOOL setGroupBits( const LLUUID& agent, const LLUUID& group, BOOL set, PermissionMask bits);
    BOOL setEveryoneBits(const LLUUID& agent, const LLUUID& group, BOOL set, PermissionMask bits);
    BOOL setNextOwnerBits(const LLUUID& agent, const LLUUID& group, BOOL set, PermissionMask bits);

    // This is currently only used in the Viewer to handle calling cards
    // where the creator is actually used to store the target. Use with care.
    void setCreator(const LLUUID& creator) { mCreator = creator; }

    //
    // METHODS
    //

    // All the allow* functions return true if the given agent or
    // group can perform the function. Prefer using this set of
    // operations to check permissions on an object.  These return
    // true if the given agent or group can perform the function.
    // They also return true if the object isn't owned, or the
    // requesting agent is a system agent.  See llpermissionsflags.h
    // for bits.
    bool allowOperationBy(PermissionBit op, const LLUUID& agent, const LLUUID& group = LLUUID::null) const;

    inline bool allowModifyBy(const LLUUID &agent_id) const;
    inline bool allowCopyBy(const LLUUID& agent_id) const;
    inline bool allowMoveBy(const LLUUID& agent_id) const;
    inline bool allowModifyBy(const LLUUID &agent_id, const LLUUID& group) const;
    inline bool allowCopyBy(const LLUUID& agent_id, const LLUUID& group) const;
    inline bool allowMoveBy(const LLUUID &agent_id, const LLUUID &group) const;

    // This somewhat specialized function is meant for testing if the
    // current owner is allowed to transfer to the specified agent id.
    inline bool allowTransferTo(const LLUUID &agent_id) const;

    //
    // DEPRECATED.
    //
    // These return true if the given agent can perform the function.
    // They also return true if the object isn't owned, or the
    // requesting agent is a system agent.  See llpermissionsflags.h
    // for bits.
    //BOOL  allowDeleteBy(const LLUUID& agent_id)   const       { return allowModifyBy(agent_id); }
    //BOOL  allowEditBy(const LLUUID& agent_id)     const       { return allowModifyBy(agent_id); }
    // saves last owner and sets current owner
    //BOOL setOwner(const LLUUID& agent, const LLUUID& owner);
    // This method saves the last owner, sets the current owner to the
    // one provided, and sets the base mask as indicated.
    //BOOL setOwner(const LLUUID& agent, const LLUUID& owner, U32 new_base_mask);

    // Attempt to set or clear the given bitmask.  Returns TRUE if you
    // are allowed to modify the permissions.  If you attempt to turn
    // on bits not allowed by the base bits, the function will return
    // TRUE, but those bits will not be set.
    //BOOL setGroupBits( const LLUUID& agent, BOOL set, PermissionMask bits);
    //BOOL setEveryoneBits(const LLUUID& agent, BOOL set, PermissionMask bits);

    //
    // MISC METHODS and OPERATORS
    //

    LLSD    packMessage() const;
    void    unpackMessage(LLSD perms);

    // For messaging system support
    void    packMessage(LLMessageSystem* msg) const;
    void    unpackMessage(LLMessageSystem* msg, const char* block, S32 block_num = 0);

    BOOL    importLegacyStream(std::istream& input_stream);
    BOOL    exportLegacyStream(std::ostream& output_stream) const;

    bool operator==(const LLPermissions &rhs) const;
    bool operator!=(const LLPermissions &rhs) const;

    friend std::ostream& operator<<(std::ostream &s, const LLPermissions &perm);

};

// Inlines
bool LLPermissions::allowModifyBy(const LLUUID& agent, const LLUUID& group) const
{
    return allowOperationBy(PERM_MODIFY, agent, group);
}

bool LLPermissions::allowCopyBy(const LLUUID& agent, const LLUUID& group) const
{
    return allowOperationBy(PERM_COPY, agent, group);
}


bool LLPermissions::allowMoveBy(const LLUUID& agent, const LLUUID& group) const
{
    return allowOperationBy(PERM_MOVE, agent, group);
}

bool LLPermissions::allowModifyBy(const LLUUID& agent) const
{
    return allowOperationBy(PERM_MODIFY, agent, LLUUID::null);
}

bool LLPermissions::allowCopyBy(const LLUUID& agent) const
{
    return allowOperationBy(PERM_COPY, agent, LLUUID::null);
}

bool LLPermissions::allowMoveBy(const LLUUID& agent) const
{
    return allowOperationBy(PERM_MOVE, agent, LLUUID::null);
}

bool LLPermissions::allowTransferTo(const LLUUID &agent_id) const
{
    if (mIsGroupOwned)
    {
        return allowOperationBy(PERM_TRANSFER, mGroup, mGroup);
    }
    else
    {
        return ((mOwner == agent_id) ? TRUE : allowOperationBy(PERM_TRANSFER, mOwner));
    }
}

//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// Class LLAggregatePermissions
//
// Class which encapsulates object and inventory permissions,
// ownership, etc. Currently, it only aggregates PERM_COPY,
// PERM_MODIFY, and PERM_TRANSFER.
//
// Usually you will construct an instance and hand the object several
// permissions masks to aggregate the copy, modify, and
// transferability into a nice trinary value.
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

class LLAggregatePermissions
{
public:
    enum EValue
    {
        AP_EMPTY = 0x00,
        AP_NONE = 0x01,
        AP_SOME = 0x02,
        AP_ALL = 0x03
    };

    // construct an empty aggregate permissions
    LLAggregatePermissions();

    // pass in a PERM_COPY, PERM_TRANSFER, etc, and get out a EValue
    // enumeration describing the current aggregate permissions.
    EValue getValue(PermissionBit bit) const;

    // returns the permissions packed into the 6 LSB of a U8:
    // 00TTMMCC
    // where TT = transfer, MM = modify, and CC = copy
    // LSB is to the right
    U8 getU8() const;

    // return TRUE is the aggregate permissions are empty, otherwise FALSE.
    BOOL isEmpty() const ;

    // pass in a PERM_COPY, PERM_TRANSFER, etc, and an EValue
    // enumeration to specifically set that value. Not implemented
    // because I'm not sure it's a useful api.
    //void setValue(PermissionBit bit, EValue);

    // Given a mask, aggregate the useful permissions.
    void aggregate(PermissionMask mask);

    // Aggregate aggregates
    void aggregate(const LLAggregatePermissions& ag);

    // message handling
    void packMessage(LLMessageSystem* msg, const char* field) const;
    void unpackMessage(LLMessageSystem* msg, const char* block, const char *field, S32 block_num = 0);

    static const LLAggregatePermissions empty;

    friend std::ostream& operator<<(std::ostream &s, const LLAggregatePermissions &perm);

protected:
    enum EPermIndex
    {
        PI_COPY = 0,
        PI_MODIFY = 1,
        PI_TRANSFER = 2,
        PI_END = 3,
        PI_COUNT = 3
    };
    void aggregateBit(EPermIndex idx, BOOL allowed);
    void aggregateIndex(EPermIndex idx, U8 bits);
    static EPermIndex perm2PermIndex(PermissionBit bit);

    // structure used to store the aggregate so far.
    U8 mBits[PI_COUNT];
};

// These functions convert between structured data and permissions as
// appropriate for serialization. The permissions are a map of things
// like 'creator_id', 'owner_id', etc, with the value copied from the
// permission object.
LLSD ll_create_sd_from_permissions(const LLPermissions& perm);
LLPermissions ll_permissions_from_sd(const LLSD& sd_perm);

#endif